Sap-stain control



Patented Sept. 25, 1945 SAP-STAIN CONTROL Roland Smith Shumard, St. Louis, Mo alalgnor to Monsanto Chemical Company, St. Louis, Mo., a corporation of Delaware No Drawing. Application February l, 1542, Serial No. 429,951

3 Gains. (Cl. 187-88.?)

The present invention relates to the protection andpresemtionoiwoodorsimilarcellulosicmm ior protection against insects and organisms such as mold and mildew, the decay organism, Lemuel trolled. and sap-stain organisms, such as the chrornogenic iungus, Cerotostomellu pilijerd. Specifically the invention relates to the use of qulnolinols (hydroxyquinolinea). partioularLv 8- quinolinol (B-hydroxyquinoline) and their derivatives and compositions containing quinolinols or their derivatives ior said purposes.

The main objects the invention are to provide a composition for destroying or inhibiting growth of organisms which cause deterioration oi wood which composition is relatively inexpensive to prepare; which does not cause substantial obiectionable staining of the wood: which is relatively free irom objectionable odors; which has exceptionally high toxic value against iungous growths and which retains its protective action over long periods oi time, even when exposed to relatively intense weathering. Other obiects and advantages of the invention, some of which are referred to specifically hereinafter, will be apparcut to those skilled in the art.

The action of various iungi in producing stain or decay in wood and cellulosic materials has long been recognized. Among the most common oilenders are chromogenie molds, the ordinary blue or sap-staining i'ungi, such as Cerotostomello pilllero, and decay organisms, such as Lenzites tmbea and Poria. incrussata. Molds and sapstain organisms are exceptionally active in relatively warm climates such as exist in the southern part of the United States and are active in green wood containing sap. Bap-stain organisms do not usually produce pronounced decomposition oi the wood in which they grow, but instead they degrade the wood for certain uses and thereby cause a reduction in the value of the lumber for 7 market purposes... Wood substances, after they have become sumclently seasoned, and so long as they remain dry, are practically immune from sap stain and general mold growth.

It has heretofore been proposed to protect green lumber during the period of seasoning, irom sapstain organisms by dibpinc. spraying, or otherwise applyin: thereto a suitable tonic substance having the property oi inhibiting or completely preventing the growth of stain organisms. Such a substance should possess a relatively large number of characteristics, some oi which are more or less the antithesis of others. The following constitutes a partial list oi such properties:

(a) The material should be inexpensive.

(b) It should not possess an objectionable odor.

(c) It should be highly toxic both to (anti which produce stain and decay in lumber and to molds.

(d) It should be substantially non-toxic to higheranimalliie.

(c) It should not produce substantial objectionable discoloration oi lumber to which it is applied.

(1) Itshouldbeoi'auchnahirethatitcanbe iormulated into aqueous solutions for application but it should be of only slight solubility and volatility when applied to lumber.

(a) It should be non-corrosive to metals or to wood.

(It) It should not operate deloteriously t0 paints and varnishes which may be applied to the finished wood.

(i) It should penetrate into or adhere to the wood with relative case. 1

Among the materials which have heretofore been proposed for the treatment oi green wood are borax. sodium carbonate and other alkalies; phenols such as creeols and wood and coal tar derivatives: ethyl mercury chloride and other mercury chloride and other mercury derivatives: chlorinated phenols and their salts. such as trichlorophenols. trichlorocresols, tetrachlorophenols, pentachlorophenol and chlorinated phenylphenols (for example, il-chloro-ortho-phenylphenol, i. e., fl-hydroxy-S-chloro-diphenyl ordchloro-o-phenyl-phenol) and their sodium salts. The chlorinated phenols have been eminently satisfactory for this use. In general, mercury derivatives are relatively inefl'ective against molds. The alkali are unsatisfactory because of their relative ineii'ectivcness against sap-stain and mold organisms, the relatively hish concentration which must be used. and their eflect upon wood when used at such high concentrations.

I have discovered that quinolinols (hydroxyquinolines) particularly a quinolinol (s hydroxyquinolinel, either in the free form or in the form oi metal salts or salts with acids, but preferably in the term or their sodium or other alkali-metal salts, are especially eiiective agents for the treatment of lumber to protect it from or prevent the attack of insects and growth 01' molds and other organisms such as the decay organism. Lenzites trobiu, and the blue-stain organisms C'eratostomclla pilflero. The alkali-metal salts or s-quinolinoi, such as sodium B-quinolinolate, and the acid salts oi B-quinolinol, such as the hydrochloride or sulfate (the latter is known as quinosol, Cryptonol, Sunoxol, and Superoll are soluble in water and when applied to noon wood or lumber,'in the iorm of an aqueous solution containing 0.5% or more of the salt, provide a treatment comparable to that obtained with a 1% aqueous solution of sodium pentachlorophenate. when used in concentrations of substantially less than 0.5%, for example. about 0.25%, the growth sap-stain oraanisms is prevented but the growth of certain molds persists although at a somewhat retarded rate.

I have also discovered that in admixture with alkslies such as borax the toxicity of the alkalimetal salts of the quinolinols is not substantially aliected, that is, it is neither substantially reduced, nor is it definitely enhanced. However, in admixture with toxic chlorinated phenols, such as sodium pentachlorophenate, the toxicitiu of both the sodium 8-duinolinolate and the sodium pentachiorophenate are enhanced, that is, the two toxics appear to mutually activate each other since the toxicity or the mixture is greater than is attributable to the sum of the individual toxicities of its components. In three component mixtures containing sodium 8-quinolinolatc. born: and sodium pentachlorophenate, the bore: produces a slight reduction in the efl'ectiveneas that would be expected from a mixture 0! sodium 8- quinolinolate and sodium pentachlorophenate without borax.

As examples or the advantages to be obtained by the use of the quinollnols and their saltaand compositions containing quinolinols or their salts for the protection or wood the following comparative results are typical Discs of green fast-growing southern yellow pine, having a diameter of about 2% inches and a thickness oi about A inch, were used. These discs 0! wood were dipped in aqueous solutions of varying concentrations or the toxics and were then allowed to drain. Four discs were treated at each concentration. The treated discs werethen' sprayed with an aqueous suspension or a culture of the stain organism, Comtostomella pilifera. The thus inoculated discs were placed in Mason jars, four to a Jar. The four discs that were placed in each jar were those which had been treated with the same concentration of the same toxic chemical and they were separated from each other by pieces of applicator sticks or other suitable wood separators. thus assuring a comlete circulation or air over all the wood surfaces. The iars were closed with a metal screw cap through which a vent about 1 inch in diameter had been punched. This vent was plugged with cotton to allow the vapors lrom the wood to escape and to permit slow evaporation oi moisture. The Jars were then incubated at a standroom with a controlled humidity R. H.) for a definite period (7 days) and the growths appearing thereon were observed.

The discs in most cases were treated with aqueous solutions containing 0.25, 0.5, 1.0 and 2.0 parts by weight oi. the toxic chemical or composition per 100 parts of water. The following solutions were used:

1. Sodium benzylphenate. The solutions were prepared from a technical mixture oi ortho and pera-benrs'lphenols, to which sui'iicient sodium hydroxide had been added to provide clear solutions. The amount of sodium hydroxide added was somewhat greater than the stoichiometrically required for the conversion of the phenol to the salt.

2. Sodium 2-chlorobenzylphenate. These solutions were prepared from a benzylated 2-chlorophenol and suflicient sodium hydroxide was added to efl'ect solution.

3. Sodium trichlorocresolate. These solutions were prepared from a trichlorocresol mixture obtained by the alkaline hydrolysis of 2, 3, 4, B-tetrachlorotoluene. Sumcient sodium hydroxide was added to convert the phenol to the sodium salt and to dissolve the phenol with the formation of clear solutions.

4. Sodium pentachlorophenate. These solutions were prepared Iron a commercial sodium pentachiorophenate containing a slight excess of 5. Sodium quinolinolate. These solutions were prepared trom s-quinolinol (B-hydroxyquinoline) towhichwasaddedaslightexcessolsodiumhydroxide over that stoichiometrically required to effect conversion of the quinolinoi to sodium salt to produce a clear solution.

d. Quinosol. The same ii-qulnolinol as in 5 was used. Builicient sulfuric acid was added to convert the quinollnol to the sulfate (quinosol).

I. Sodium pentachlorophenate 50 %-borax 50 mixture. The solutions were prepared from a mixture 01' equal p rts by weightof sodium pentaohlorophenate and bore: (NEIBQOLIOIHO).

I. Sodium s-quinolinolate 50%borax 60% mixture. The solutions were prepared from materials hereinabove described so as to contain equal parts by weight oi' sodium s-quinolinclate and borax.

0. Sodium I-quinolinolate 50%-sodium pentachlorophsnate 60% mixtures. The solutions were prepared from the materials hereinabove described so as to contain equal parts by weight oi sodium s-quinolinolate and sodium pentachlorophenato.

10. Sodium s-quinolinolate 33%%sodium pentaohlomphenate attic-born 33%% mixture. The solutions were prepared from the ma. terials hes-emabove described so as to contain equal parity by weight 0! sodium B-quinolinolate. sodium pentachlerophenate and honor.

The results after a period of incubation of 7 days at 20 C. oi the above solutions at concentrations corresponding to 0.25%, 0.5%, 1% and 2% of the toxic or mixture of toxics were as follows. In all these results the molds referred to are those naturally occurring with and contaminating the wood. Experience with these discs has shown a relatively uniform contamination and it is therefore not necessary to artificially inoculate the samples with mold.

The results were tabulated as in Table I following. The "per cent area stain" is the average estimated stained area oi the cross section or the and temperature (26 C. in these results) in a four discs (eight areas) in each treatment,

s,sss,ve4 3 Tobie L-Staia and mold control with various treatments asdmemmmmnamoummummsmi InTahlelItheresultsiromTs-hlelarear- 25 ranged to show the minimum concentrations treatins solutions oi the various compositions which are required to provide control of stain growth and superficial mold srowth. Prom Tablenitwillbeapparentthatallcomposltions so containing qulholinoi derivatives (8, 6, 6, D, 10) are as effective in controlllns stain as sodium pentachlorophenate alone or mixed with an equal weight of borax (4 and 7) and that the best compositions are those in which the quiuolinate is mixed with a chlorinated phenol (9). It is also to be observed that at equal concentrations the quinoiinolate is more elective for stain control than sodium pentachlorophenate and that sodiurn pentachlorophenate is more efiecflve for mold control than the quinolinolate (compare 4 and but that a lesser quantity oi a mixture oi the two (see 9) can be used to provide complete control against stain and mold than either alone. It must be appreciated that the ioresoinz values in Table 11 apply only under the conditions .de scribed previously, that is, when both types of organisms are present.

Table [IF-Minimum concentration of treating solution required to provide control Superfi- Compomkm Btsin eisl mold Psi on! Per an: 1 Sodium beusylphenste .7 ll. 6 2 Sodium pchlorohemylphenate. 10 0. I 3 Sodium trichloroereeolate 1.0 0.5 4 Sodium tachlorophenate. 2. 0 0. 2i! 5 Sodium milnolinolate .l 0. 2! L0 6 $1 "'"fii""il""6?'ss% u um ac oro ens 7 Borax mmoriolfiol 8 Sodium squiuolinolste 60%... o m 9 Borax 50% Sodium B-quinolinolate 50%. o 0 Sodium taohlorophenate 50% 8odlumm1lnolinolste33}%. 10 Sodium taohlorophenste 385% 0.5 to

mow

In using the invention the wood or green lumher may be treated by any or the conventional methods for application oi sap-stain chemicals. Thus, the compositions oi the present invention may be applied in the form oi solutions either by spraying, brushing, dipping or pressure impreznation. The quinollnol may be precipitated on the wood in the free iorm or in the term oi Concentratioucltreatlngsolution Area Area Area mm mm 7 mm Percent PM hug? No 81 No... 7 No.

94 do.... 76 .-.do.. Do. '41 4- OJ 0 0 m 1123? a Z a" he 0 o vy.- 0 Light... 0 Do.

I) No I No 0 Heavy.. 0 ...do.

0 No u do.....

0 Light'.. 0 Light salts oi heavy metals, if desired, by a second treatment with a solution oi a salt 01' a heavy metal. The concentration of the solutions to be used will be dependent to a great extent upon the degree oi control desired and the toxicity of the composition used. but will be in general be from about 0.25% to 2.0% or higher. In the case of a composition such as ll hereinabove. a concentration of 0.25% to 0.5% is senerslly adequate to provide a greater desree of control than 35 is generally necessary in the held.

The compositions for the treatment 0! wood to prevent sap-stain and mold growth contemplated by the present invention are those comprising a quinolinol or a metal or acid salt there- 40 of, particularly B-quinolinol and its sodium salt.

Preferred compositions of the invention are those which comprise the qulnolinol or alkali-metal salt thereof, particularly sodium B-quinollnolate, in admixture with other toxic chemicals such as chlorinated phenols or salts thereof, ior example,

sodium trichlorophenates, sodium tetrachlorophenates, sodium pentschlorophenate, sodium trichlorocresolates, sodium tetrachlorocresols, and other sodium salts oi chlorinated oresols and so higher alkylated phenols. sodium, Z-chloro-G- phenylphenate and similar sodium salts or chlorinsted phenylphenols. The compositions of the present invention may also include adiuvants such as wetting as'onts, for example, alkylated es aromatic sulionic acld salts such as sodium dodecylbenxenesuli'onate, sodium butyldiphenylsniionate, and the like, and other conventional insredients.

My invention is directed to the use 0! quinoliw hols, either in the tree form or in the form of metal or acid salts. The invention h directed specifically to the preferred use of B-quinolinol derivatives, particularly the sodium salt and the sulfate (quinosol), but other isomers such as ooialphaor z-hydroiwquinoline (2-quinolinol or carbostyril) betaor S-hydroxyquinoline (8- quinolinol), gammaor 4-hydroxyquinoline (4- quinolinol or kyanurin), anaor o-hydroxyquinoline to-quinolinol), paraor fl-hydroxyquinoline (G-quinolinol) and metaor 'l-hydronqulnollne ("l-quinolinol), chlorinated quinolinols and slkylated quinolinols. such as S-chloro-li-quinolilol, 5.7 dichloro-B-quinolllol, o-methyl-e-quinolilol, o-methyl-s-quinolilol, and 'l-chloro-o-propylqulnolilol, and their acid and metal salts may be mod. The sodium salt is termed by the addition ctsodiumhrdroxideorsodium col-boosts tothe qulnclinol. wheres! the sold alts ere termed by eddies on eoid,.!cr example. hydrochloric acid orsuliurioaciitcthequtnclinol. l 'oruseinthe tcleim:

1,,Ihe methodofitreotins to preventthegrowtholmcidssndsep-stsiningtungi thereomwhichcomwisesspolyinltothewood s. solution 0! s mixture ccutsininz cs its active constituents sodium l-quinoiiuolete and sodium pentlchhi'ol hm.

2. A- green-wood mold end sop-stein control scent-which ccntoins as its active constituent c mixture of sodium Muinolinolste and sodium p'entechlorcphenete.

it h to be undentocdthetthsinvention is not 7 limited theretosndthetvorietions sndpodiiicoticnsmuhemedetheremtosdapttheiovencioutcspecincuseswithoutdepertinssuhstantisllri'romthesmendedclsims;

SJIhsmethodcttreeti greenIcodtom-event the growth of molds end sop-staining mnli thereon. which comprises ewlyinl to the wood s solution 01' e preset-votive consisting oi sodium l quinoiinciote and sodium pentechlorcphenete.

* ROLAND B. SHUIIARD.

' CERTIFICATE OF CORRECTION Patent No. 2,555,76h.

September 25 1911.5.

Ronni: SliI'l'H smmmn.

it is hereby certified that error appears in the printed specification of the above mmbered potent requiring correction as roll-owe: Page 1, secand column, lines 31; end 55, strike out the words page 2, second column, line 114, for thsnthe read --than that";

the said letters Paterit should. be read with this correction therechlcride and thfl t and other mercury in that the we may conform to the record or the casein the Patent Office.

Signed and sealed this let-day ct Jam-Lory, A. D. 1914.6;

Leslie Frszer First Assistant Commissioner of Patents.

mod. The sodium salt is termed by the addition ctsodiumhrdroxideorsodium col-boosts tothe qulnclinol. wheres! the sold alts ere termed by eddies on eoid,.!cr example. hydrochloric acid orsuliurioaciitcthequtnclinol. l 'oruseinthe tcleim:

1,,Ihe methodofitreotins to preventthegrowtholmcidssndsep-stsiningtungi thereomwhichcomwisesspolyinltothewood s. solution 0! s mixture ccutsininz cs its active constituents sodium l-quinoiiuolete and sodium pentlchhi'ol hm.

2. A- green-wood mold end sop-stein control scent-which ccntoins as its active constituent c mixture of sodium Muinolinolste and sodium p'entechlorcphenete.

it h to be undentocdthetthsinvention is not 7 limited theretosndthetvorietions sndpodiiicoticnsmuhemedetheremtosdapttheiovencioutcspecincuseswithoutdepertinssuhstantisllri'romthesmendedclsims;

SJIhsmethodcttreeti greenIcodtom-event the growth of molds end sop-staining mnli thereon. which comprises ewlyinl to the wood s solution 01' e preset-votive consisting oi sodium l quinoiinciote and sodium pentechlorcphenete.

* ROLAND B. SHUIIARD.

' CERTIFICATE OF CORRECTION Patent No. 2,555,76h.

September 25 1911.5.

Ronni: SliI'l'H smmmn.

it is hereby certified that error appears in the printed specification of the above mmbered potent requiring correction as roll-owe: Page 1, secand column, lines 31; end 55, strike out the words page 2, second column, line 114, for thsnthe read --than that"; the said letters Patent should. be read with this correction therechlcride and thfl t and other mercury in that the we may conform to the record or the casein the Patent Office.

Signed and sealed this let-day ct Jam-Lory, A. D. 1914.6;

Leslie Frszer First Assistant Commissioner of Patents. 

